Slow sailing in the soup

About 15 inbound flights were diverted from Salt Lake City on Thursday as heavy fog and the haze from an inversion limited visibility.

SALT LAKE CITY — Airport officials were on "fog alert" Thursday, with some flights delayed or diverted.

Foggy conditions were expected to continue through this morning, creating potential hassles for airline passengers and drivers on some roadways.

Airport spokeswoman Barbara Gann stressed commuters destined for the air should check with appropriate carriers frequently to determine if travel schedules have been impacted.

"As the air gets cooler and the ground gets cooler," the potential for fog was expected to escalate late Thursday, Gann said.

A swath of fog settled over the Salt Lake City International Airport Thursday morning, leading to the diversion of about 15 inbound flights and the "grounding" of outbound regional jets.

Another slowdown occurred between 5:40 and 8 p.m., causing delays of 15 minutes to two hours but no diversions, Gann said. Wendover Airport was closed Thursday evening and had one flight diverted to Salt Lake, she said.

The soupy condition is not unusual for the airport during this time of year, Gann said, and could easily happen again.

"This typically happens once a year in December or January and is a phenomenon that we deal with annually," she said.

The fog lifted enough at about 10 a.m. for the airport to return to normal operations, but the ensuing ripple effect of delays continued through the afternoon.

A dense fog advisory is in effect for much of northern Utah through 11 a.m. today, reducing visibility to a quarter-mile or less along I-80 and the Legacy Parkway near the Great Salt Lake, and on I-15 in Davis County.

The fog adds to the inversion trapping dirty air in the valleys along the Wasatch Front, with red air quality alerts all the way from Cache to Utah counties today and Saturday.

While airport officials used to do "cloud seeding" in attempt to minimize the impact of fog, that was eventually proven non-effective and has since been abandoned.

The result is that airports must wait out the murky conditions especially for those regional jets, which do not have instruments that are as sophisticated as the bigger airliners.